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    <meta charset="UTF-8">
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    <title>div和span标签</title>
    
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<body>
    <div>div独占一行，后面的内容自动换行</div>123
    <div>div独占一行，后面的内容自动换行</div>123<br/>
    <span >A</span>
    <span>B</span>
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